* AcePilot: Pilot of both Bio Jet 1 and the first Japanese space shuttle.* FriendToAllLivingThings: With his SpeaksFluentAnimal powers.* LawOfChromaticSuperiority: Shirou can understand animals, but nobody else is shown to have unmorphed powers. [[spoiler: He's also the only one to be directly linked to the Dr. Man part of the plot through his father.]]* TheLeader: Of the Biomen.* PlayingWithFire: [[FlamingSword Fire Sword]]

![[color:green:Takasugi Shingo/Green Two]]

* BadassDriver: Primary driver of the [[CoolCar Bio Turbo]].%%* TheBigGuy:* BlowYouAway: Hurricane Sword%%* GeniusBruiser* TheLancer: He is the NumberTwo after all, but he really cements himself in this position once Mika bites it.* PrecisionGuidedBoomerang: ''Green Boomerang''%%* TheSmartGuy

![[color:blue:Nanbara Ryuuta/Blue Three]]

* {{Delinquent}}: He used to be a delinquent in his teen years, but was inspired to change his ways. His first encounter with Prince reminded him of those times.%%* FragileSpeedster%%* KidAppealCharacter * PunnyName: His Bioman codename is a pun on how the Japanese pronounce "Bruce Lee".* ShockAndAwe: ''Elec Sword''* TheSneakyGuy: His years of diving have made him very nimble and thus he is very skilled in stealth techniques.

![[color:gold:Koizumi Mika/Yellow Four I]]

* AntiHero: [[ClassicalAntiHero Type I]].* FauxActionGirl: In her nine episodes, she doesn't do much fighting.* ForgottenFallenFriend: No mention of her is made after her death.%%* FourIsDeath: * HeroicSacrifice* KilledOffForReal%%* RealLifeWritesThePlot: The main writer had plans for Mika that [[WhatCouldHaveBeen ultimately went unrealized]] after the actress left the series so early.* ShockAndAwe: ''Thunder Sword''.* TakingTheBullet%%* TomboyAndGirlyGirl: Tomboy to Hikaru's Girly Girl. (Originally)* WeHardlyKnewYe: Only appears unmorphed in the first six episodes.

![[color:gold:Yabuki Jun/Yellow Four II]]

* ActionGirl: Very much so, especially since her actress did her own stunts.%%* TheBigGuy: %%* LegacyCharacter* MartialArtsHeadband: You don't ever see Jun without wearing one (and it fits [[TheBigGuy her role]] too). [[spoiler:Even one episode had this weaponized by the villains by replacing it with a time bomb!]]* ShockAndAwe: Thunder Sword%%* {{Shorttank}}* TheStraightAndArrowPath: Is the only one of the Biomen to wield a physical weapon - a bow.%%* TomboyAndGirlyGirl: Tomboy to Hikaru's Girly Girl. (Replacement)* WhyDidItHaveToBeSnakes: Spiders.

!Peebo* GenderFlip: Even though he's technically a sexless automaton, he addresses himself as a male in the Japanese original. In the English dub however, he was made female.* RobotBuddy

!Bio Robo* CombiningMecha: Composed of two jets (Bio Jet 1 and Bio Jet 2).* HumongousMecha* MechanicalLifeform: It is shown that Bio Robo has a will of its own when it runs away during Silva's first appearance.

'''Anti-Bio Union'''!Bio Hunter Silva* BigBad: He reappears as one of the main antagonists of Film/KamenRiderXSuperSentaiSuperHeroTaisen.* BladeBelowTheShoulder: Both which can be fired like arrows.* CatchPhrase: Hakai! Hakai! Hakai! (Destroy! Destroy! Destroy!)* TheDreaded: He possesses Anti-Bio Particles that are more powerful than those used [[spoiler:to kill the first Yellow Four]] (Even though he doesn't manage to kill any Biomen with them). Peebo had a very good reason to fear him.%%* EvilLaugh* {{Expy}}: Based on Series/{{Kikaider}}'s nemesis Hakaider.* HeroKiller: * HumongousMecha: Pilots one.* WildCard